This invention relates generally to a program event recording program debugging tool, and more particularly to utilizing a single hardware feature for the checking of PER branch instructions and PER store instructions within a common dataflow configuration.
Program event recording (PER) is a program debugging tool that is implemented in conjunction with IBM's® z/architecture® mainframe computing systems. In operation, PER identifies the occurrence of the execution of a successful branch instruction, wherein PER provides the option of requiring that an event occur only when a branch-target location is within a designated storage area (a PER branch instruction). PER also provides for the fetching of a designated instruction from a predetermined storage area (a PER fetch instruction) in addition to allowing for the contents of the designated storage area to be stored at a designated storage area (PER store instruction). PER event information is provided to a program by means of a program interruption, wherein the cause of the interruption is identified in the interruption code.
Within a PER environment, a designated storage area is identified by two control registers, wherein a first register indicates the start of the storage area and a secondary register indicates the end of the designated storage area. The designated storage area specified by the first and secondary registers is referred to as the PER range. Presently PER branch and store instructions are executed within differing hardware dataflow configurations.
It would be advantageous to be able to unify the hardware dataflow operations within a single hardware feature in regard to PER Branch and Store instructions.